Lighted display units

ABSTRACT

This invention relates to improvements in lighted display units of the kind in which individual characters are associated with one another to form a composite display. In the embodiment described, the unit is modularized in part with each module being specific to one character so that a composite display is formed by combining modules. There is provided, with respect to each character to be displayed, a front panel section including indicia portions which when lighted provide a representation of a selected character, a heat sink, and a lamp socket and socket holder assembly which is provided with lamp sockets oriented to underlie the individual segments of the character to be displayed. The heat sink and light shield unit is sandwiched between the front panel and the socket holder and is provided with individual bores of size to accommodate a single lamp bulb in alignment with the socket for that bulb and the indicia section to be lighted thereby.

United States Patent William J Lang Primary Examiner-Donald J. YuskoOrange, Calif. Assistant Examiner-Michael Slobasky [211 App]. No.735,255 Attorney-Harvey C. Nienow June 7, 1968 [45] Patented Apr. 6,1971 symbol 5 ABSTRACT: This invention relates to improvements in Orangelighted display units of the kind in which individual characters areassociated with one another to form a composite display. In theembodiment described, the unit is modularized in part [72] lnventor 221Filed [73] Assignee 54] LIGHTEDDISPLAY UNITS 7 Claims, 7 Drawing Figs.with each module being specific to one character so that a compositedisplay is formed by combining modules. There is provided ,with respectto each character to be displayed, a front panel section includingindicia portions which when lighted provide a representation of aselected character, a heat sink, and a lamp socket and socket holderassembly which is 8 8 m7wmm7 3 3 5 0 0 4 4 m w. C m 5 mk U IF N. W 5 55l. [l

provided with lamp sockets oriented to underlie the individual segmentsof the character to be displayed. The heat sink and light shield unit issandwiched between the front panel and the socket holder and is providedwith individual bores of size to accommodate a single lamp bulb inalignment with the socket for that bulb and the indicia section to belighted thereby.

340/381 Naylor.......................... 340/378 Patented April 6, 19712 Sheets-Sheet 1 FIG.2

MM 5 TA N WL V m J 7 M LIGHTED DISPLAY UNITS This invention relates toimprovements in lighted display units and it relates particularly tounits which display discrete characters as a combination of individualindicia segments in which characterization is altered by selectivelighting of the individual indicia sections.

An object of the invention is to provide a display unit for instrumentand computer panels, for control boards, checkout systems and a widevariety of other applications where illuminated digital displays arerequired. It is an object of the invention to provide a display unit:which can be produced in miniaturized form; which displays allcharacters, whether numerical or alphabetical or symbolical, in the sameplane; which displays all characters with the same luminosity; whoselight elements are conveniently replaced; and which can be manufacturedreadily at minimum cost.

Another object of the invention is to provide a display unit theelements of which are produced in a modular form permitting combinationof characters in easily readable and recognizable form without unduespacing between adjacent characters. In this connection it is an objectof the invention to provide a display unit module in which thecharacters are formed of individually lighted indicia segmentspermitting the representation of different characters by theillumination of selected segments and failure to illuminate others.Another object of the invention is to provide a display unit modulewhich incorporates provision for representing a decimal point or degreemark without altering the pattern of spacing between adjacentcharacters.

These and other objects and advantages of the invention which willhereinafter appear are realized in part by the provision of an indiciapanel formed with indicia sections capable of transmitting lighttransversely through said panel but being otherwise opaque there beingseven light conducting sections each'having the form of line segments,the line segments of three sections being arranged in spaced parallelrelation to define the top, center, and lower horizontal portionsrespectively of a figure 8 and the other sections being arranged inpairs to define the sides at the upper and lower sections of the figure8 by means associated with each indicia section respectively fordirecting light to the indicia section with which it is associated andto no other; and by means for energizing selectively the light sourceassociated with each indicia section. Also, the advantages and objectsof the invention are realized in part by the provision on the indiciapanel formed with indicia sections capable of transmitting lighttransversely through the panel, but being otherwise opaque together witha lamp socket and a lamp socket holder assembly comprising a lamp socketholder and a plurality of lamp sockets mounted on one face thereof anddisposed in positions corresponding to the position of the indiciasections of the panel; by the provision of a lamp shield and heat sinkunit interposed between the indicia panel and the lamp socket holderflush against the face of the panel, the lamp shield being provided witha plurality of through openings one for each indicia section of thepanel and underlying a respectively associated indicia section; and bythe provision of lamps associated with the lamp sockets and disposed inrespectively associated ones of the bores or through openings of thelamp shield.

A preferred form of the invention has been selected for illustration inthe drawings. It is to be understood that various modifications may bemade in the embodiment shown and that other embodiments are possiblewithout departing from the spirit of the invention or the scope of theappended claims.

In the drawings:

FIG. I is an isometric view of a lighted display unit embodying theinvention, comprising several display modules nested together in sideby-side relation with portions of the several modules shown fragmentedor in section to illustrate details of their internal construction;

FIG. 2 is a view in front elevation of the panel of a lighted displayunit embodying the invention;

FIG. 3 is a view in front elevation of a lamp shield and heat sink unitemployed in the modules of FIG. 1;

FIG. 4 is a view in rear elevation of a fragment of the mounting plateof the display unit of FIG. I through the opening of which the rear faceof a lamp shield and heat sink unit is visible;

FIG. 5 is a cross-sectional view taken lengthwise through the elementsof one module of the unit taken on line 5-5 of FIG. 1;

FIG. 6 is a cross-sectional view of a fragment of a front panel and heatsink assembly taken on lines 6-6 of FIG. 5 and showing the light path bywhich a display indicia is illuminated by its respectively associatedlamp;

FIG. 7 is a view in front elevation of the connector housing section ofa display unit module. Referring to FIG. I of the drawings, there isshown a lighted display unit generally designated I0 and consisting of anumber of module elements, one set for each character to be displayed,which are mounted upon a common indicia panel and upon a common mountingplate.

In FIG. I the central portion of the indicia panel has been broken awaybut the left end and the right end of the panel are visible and they aredesignated by the reference numeral 12. Immediately behind the frontpanel 12 there is mounted a lamp shield and heat sink unit. One suchheat sink unit is provided behind each character to be displayed on thefront panel and it is one of the elements of the set of module elementsassociated with that character. In FIG. 1 the lamp shield and heat sinkunit at the leftmost character is designated by the numeral 14. The nextadjacent shield and heat sink unit is designated 16. Part of that unithas been broken away. The heat sink units of the intermediate moduleelement sets have been omitted to make visible the structure that liesbehind. However, a portion of the rightmost heat sink unit 18 is visiblein FIG. I.

The front and rear faces of the heat sink units are parallel and therear face of the flat indicia panel 12 lies flat against the .frontfaces of the several heat sink units. The rear faces of these heat sinkunits lie flat against the flat mounting plate 20 -which liesimmediately behind them. Immediately behind the mounting plate 20 thereare mounted a number of lamp socket holder and lamp socket assemblyunits. One of these units is provided for each character to be displayedon the front panel.

The leftmost assembly is designated by the reference numeral 22. Itsforward and rear faces are parallel and it is mounted with its forwardface flush against the rearward face of the mounting plate 20 so that itlies immediately behind the heat sink unit 14. The width and the heightof the assembly 22 are the same as the width and the height of the sinkunit 14. They need not be, and in fact are not, of equal length. Thelamp socket holder and lamp socket assembly 24 is disposed adjacent theassembly 22 immediately behind the mounting plate 20 in alignment withthe heat sink unit 16 of the second module set from the left in FIG. 1.Next to the right of assembly 24 is a similar assembly designated 26which has been sectioned so the full length of several of its sockets(designated 28, 29 and 30), can be seen in assembled position. Thesesockets are adapted to receive the terminals of light bulbs or lampsthree of which are visible in the second module from the left. Theselamps, which are designated 32, 33 and 34, have their terminals insertedin the sockets which form a part of the socket holder and socketassembly 24. The lamps extend forwardly through an opening, a singleopening 36 which accommodates all of them, into a respectivelyassociated one of the bores which extend through the heat sink 16. Thelamp socket holder and lamp socket assembly of the rightmost module isvisible, although fragmented, in FIG. 1 where it is designated by thereference numeral 38.

The module associated with each character further comprises an outputterminal assembly housing. Interconnection between the terminals of theseveral sockets of the socket assemblies through outlet terminals orleads is accomplished within the cavity of these output tenninalhousings. The leftmost terminal housing lies behind assembly 22 and isdesignated by the reference numeral 40 in FIG. 1. The housing associatedwith assembly 24 (which is connected to the rearward side of assembly24) is designated 42 in FIG. I. The housing behind assembly 26 isdesignated 44 and the adjacent housing, which is broken so that itsinterior is visible, is designated by the numeral 46. In the case ofhousing 46 the external circuitry comprises a ribbon 48 consisting of aseries of insulated conductor wires arranged side by side and securedtogether to form a flat ribbon of conductors. A T-shaped block 50 hasbeen molded over the ribbon of conductors. The block 50 fits within anopening at the rearward side of the housing 46 and is held in positionwithin the cavity of the housing by the crossbar section of the T.Alternative constructions and connecting means are available fordifferent applications. The arrangement in FIG. I is shown onlyschematically because the particular connection method forms no part ofthe instant invention. The connector housing of the rightmost modulelies behind the lamp socket assembly 38 and is designated by the numeral52. The output circuit construction at the rearward side of housing 42,44 and 52 are similar to the construction, consisting of the ribbon 48and block 50, at the rear output end of the terminal housing 46.

An additional section designated 54 is shown connected to the rearwardside of the connector housing forward 40 of the leftmost module set. Aswill be explained below, and as illustrated in FIG. 1, certain of thecharacters to be displaced at the display panel are formed byilluminating selected ones of a number of line segments which, when allare lighted, form the figure 8. For examplefin FIG. 1 at the right endof the display panel 12, the portion of the panel which is associatedwith the heat sink I8 is formed with seven line segments arranged inthree rows at the left, center, and right of that section respectively.The center or second row comprises three line segments extendinghorizontally and arranged one above the other in parallel. Thesesegments form the top 56, middle 58,

and lower 60 portions of the figure 8. In the first row there are twoline segments arranged in a line at the left of the segments 56, 58 and60. Their direction is perpendicular to the three segments of the secondrow. The uppermost of these first row segments is numbered 62, extendsfrom the upper segment 56 to the middle segment 58 of the second row.The lowermost segment 64 of the first row extends from the middle 58 tothe lower segment 60 of the middle row. There are two segments in thethird row; they are arranged in line at the right of the right ends ofthe threesegments of the second row. The uppermost 66 of these two linesegments extends from the upper horizontal bar or line segment 56 to themiddle horizontal line segment 58 and the lower segment 68 of the thirdrow extends from the end of the middle horizontal line segment 58 to theend at the right of the lower line segment 60. The bores or holesthrough the heat sink 18 are arranged one behind each one of these linesegments and a lamp is contained in each of the bores. The line segmentportions of the display panel are transparent and each will beilluminated and will transmit light when the lamp behind is illuminated.If all of the lamps behind the line segments 56, 58, 60, 62, 64, 66 and68 are illuminated the numeral 8 will be clearly visible. If the lampbehind lamp segment 58, the center segment, is extinguished and theremaining line segments are illuminated then the character zero will bedisplayed. If the line segment 58 is illuminated along with linesegments 62, 64, 66 and 68 and only line segments 56 and 60 areunilluminated, then the character displayed will be the letter H. Insimilar fashion, all of the numerals from -9 and many letters may berepresented by illumination of some line segments and not illuminatingothers. The illumination or nonillumination of the several lamps may becontrolled by electronic logic circuits. The unit 54 of the first moduleset, which additionally comprises the heat sink I4, the socket assembly22, and the connector terminal hous ing 40, contains electronic logiccircuitry by which selected ones of the lamps in heat sink I4 and socketassembly 22 are illuminated and extinguished upon the application ofsignals to the electrical input circuit ribbon 70 extending from therearward end of the section 54.

A module is defined as the combination of the indicia panel section, theheat sink unit, the mounting plate section, the socket holder and socketassembly, the connector casing, and if there is one, the logic circuithousing all associated with a set of indicia for displaying onecharacter. The heat sink units, the lamp socket holder and socketassemblies, the connector housing and the logic circuit housings allhave the same height and same width and these units all have flatforward and rear faces so that these elements of a module set may beassembled end-to-end with one another and so that module sets may beassembled, side-to-side like building blocks to form larger assembliesas illustrated in'FlG. I when-more than one module set is employed. Theyare arranged side-by-side in which case the several indicia panelsections of the modules may be com bined into a single unit. When thereis more than one section their mounting plates are normally combinedinto a single mounting plate which may comprise the panel or subpanel ofthe instrument or control unit on which the display is to be mounted.

FIG. 2 is a front view a three module display unit in which the indiciapanel section of the several units are not combined into a single panel.Instead only two, the panel associated with the center module and thepanel associated with the rightmost module, are combined into a panel72. The display panel of the leftmost unit is separate and individual tothat unit. The indicia of each half of the panel 72 are divided intonine individual indicia sections. Seven of these indicia sections arearranged in a cluster which define a figure 8 as previously described.The eight indicia section 74 of the indicia panel section associatedwith the central module set represents a decimal point and is designated74. The ninth indicia section of that same panel section is designated76 and represents a degree mark. It will be apparent upon an examinationof FIG. 2' that the cluster of line segments, which collectively aredesignated 78 in the drawing, associated with the rightmost module setof FIG. 2 are closely adjacent to the cluster of line segments,collectively designated 80 and associated with the central module set.The two characters are closely proximate to one another despiteinterposition between them of the decimal and degree marks.

This feature of the invention is provided by combining the light shieldarrangement in which light from each lamp is applied to one indiciasection and no other with a module construction in which the upper andlower sections of each segment of the module is offset laterally fromthe central portion which contains, or is aligned with, the cluster ofseven line segment indicia sections.

This offset arrangement is apparent in FIG. 3 which is a view in frontelevation of a light shield and heat sink unit. The unit selected forillustration in FIG. 3 is the heat sink unit 18 of FIG. I. It isprovided with seven bores arranged in a cluster in the central region ofthe unit. When assembled with the indicia panel 12, bore 81 underliesthe line segment 56 and bores 82, 83, 84, 85, 86 and 87 underlie linesegments 62, 58, 64, 60, 68 and 66 respectively. The upper section 88and the lower section 90 of the heat sink unit 18 are offset laterallyto the right relative to the central portion of the unit which containsthe bores 82, 83, 84, 85, 86 and 87. Bore 92, at the lower right, andbore 94, at the upper right in FIG. 3, underlie the decimal pointindicia segment of FIG. 1 and the degree mark indicia section 96 of FIG.1, respectively. These two bores, 92 and 94, extend into the upper andlower laterally displaces sections 90 and 88. It is apparent in FIG. 3that the right face of the heat sink unit has a shape which is theinverse of the shape of the left face of the unit. The other sections ofeach module, specifically the socket holder and socket assembly and theconnector housing, have their side faces similarly shaped so thatadjacent modules may be nested one against the other to form ahorizontal row of module sets as depicted in FIGS. I and 2. It is thisarrangement that permits the cluster of indicia sections of one moduleto be placed closely adjacent the cluster of indicia modules of theadjacent module despite the interposition of the decimal point anddegree symbol between them. That the elements of adjacent modules nesttogether is illustrated in FIG. 1 and by the dash lines of FIG. 2.

To illustrate that indicia panels having other than the seven barcluster arrangement may be employed and in fact are compatible with suchmodules and that the invention is not limited to the specific indiciaherein specifically described, the display unit of FIG. 2 includes, atthe left, an indicia panel incorporating and alternative form ofindicia, in this case the letters N and S.

Means are provided for fastening the indicia panel and the shield andheat sink unit to the mounting plate in a manner permitting theirremoval from the indicia plate side of that assembly. Any convenientmeans may be employed. In the preferred embodiment illustrated in thedrawings, machine screws extend through openings in the indicia paneland the heat sink unit to threaded engagement with the mounting plate.Two such machine screws, identified by the reference numerals 97 and99'are visible at the right end section of the indicia panel in FIG. 1.That holes are provided through the heat sink unit and in the mountingplate to accommodate these machine screws is illustrated in thesectional view of heat sink unit 16 in FIG. 1 where the upper hole isdesignated by the reference numeral 100. The socket housing and socketassembly units and the connector casing units (and the logic circuithousings when used) are secured to the mounting plate in a way thatpermits their removal from the rear of the plate. Any convenient meansmay be employed. In the embodiment illustrated this means comprises amachine screw which is inserted from the rear end of the module forwardthrough holes in the several elements of the module to threadedengagement with the mounting plate 20. This arrangement is illustratedin FIG. 5 which shows a cross-sectional view through one module taken onthe plane of the rear mounting flat headed machine screws 101 and 102.These screws extend through the connector housing 52 and through thesocket housing and socket assembly 38 into the mounting plate 20 wherethe end of the machine screws are threadably engaged. This arrangementof the fastening means permits removal of the indicia panel and heatsink units from the front of the assembly whereupon the lamps are easilyaccessible from the front of the unit.

The embodiment illustrated is designed for miniaturized production. In atypical production unit the height of the indicia panel is only 0.625inches. It will be apparent that in a unit of that size the several lampbulbs associated with each character are very small and are installedvery close together. To facilitate their removal without the need forspecial tools, the opening in the mounting plate through which all ofthese light bulbs extend is made sufficiently large to accommodate allor most of the bulbs in a single opening. FIG. 4 is a view of the rearside of the mounting plate 20 which shows the outline of its opening 36through which the rear face of the heat sink unit 16 is visible.Advantageously, as shown, the opening 36 is shaped to provide access toall of the bores or holes of the heat sink unit 16 which are intended oradapted to accommodate one of the lamps.

Returning to FIG. 5 of the drawings, several important features of theinvention are illustrated. The section line is arranged so that theindicia sections 56, 58 and 60, and their underlying structures, arevisible. The various elements of the module are assembled sandwich likeso that the indicia panel 12 overlies the heat sink unit 18 whichoverlies the mounting plate 20. The socket assembly 38 is sandwichedbetween the mounting plate 20 and the connector housing 52. In theassembly 38, the lamp socket associated with the upper openingunderlying the indicia portion 56 has been omitted to show that thesocket housing is provided with a through bore to aceommodate thesocket. The bore 104 has uniform diameter throughout its length exceptthat it has reduced diameter over a small portion 106 of its lengthclose to its forward face. The effect of this reduction in diameter isto provide a shoulder 108 against which the socket structure may beseated. In this embodiment, the lamp socket is arranged to accommodatelamps whose external terminals comprise a pair of parallel wiresextending rearwardly from the lamp base. The socket comprises two metaltubular sleeves, one for each lamp conductor wire, which are retainedwithin an insulating sleeve which is generally cylindrical member whichis provided with two, parallel, through openings along its length toaccommodate the metal connector sleeves. The insulating cylinder isshown in assembled position within the socket housing opening whichunderlies the indicia portion 58. This insulating cylinder is designatedby the numeral and is shown to comprise two parallel openings 112 and114. In the lowermost of the three openings of the socket assembly 38(i.e., the opening behind the indicia section 60) the assembly iscomplete in that it includes the insulating sleeve 116 and two metalconnector sleeves 118 and 120 inserted one in each of the two openingsof the insulating sleeve. The two sleeves are lanced lengthwise in aforward section of their length and the lanced portion is bent inwardlyto a position in which it has frictional engagement with the terminalwires of the lamp. In FIG. 5, the connector sleeve 20 has a lancedportion 122 which engages frictionally the terminal wire 124 of a lamp126. The other terminal wire of the lamp has frictional engagement witha similar section of the connector sleeve 118.

The connector sleeves are sufficiently long so that they extendrearwardly from the socket housing and socket assembly unit 38 into thecavity of the connector housing 52. Means are provided for connectingthese rearward ends of the connector sleeves to external circuit wires126 which are held together in fixed position within the connectorhousing by a T-block 128. As previously explained, the showing of thisconnector arrangement is schematic and is intended to be representativeof a variety of well-known constructional arrangements.

The construction of the connector housing 52 is shown in FIG. 7 which isan elevational view taken from the front. The sidewalls of the housingdefine a relatively large cavity in which the connection isaccomplished. The opening 130 in the rear wall of the casingaccommodates the T-block 128 or other constructional arrangementaffording access to external circuitry.

The lamp cluster associated with indicia panels which include the sevenline segment indicia section configuration, whether with or withoutadditional indicia segments representing decimal and degree marks,produces a relatively large quantity of heat that must be dissipatedefficiently to insure long life for the lamps. Further and as previouslyexplained, there is a need to limit the application of light from eachlamp to its respectively associated indicia portion and to no other.These two functions, heat removal and shielding, are accomplishedprimarily by the light shield and heat sink unit which comprises a blockof heat-conductive material which is provided with a separate throughbore to accommodate each lamp. The several bores through the unit havesize permitting easy placement and removal of the unit over and from thecluster of lamps so that it presents no impediment to easy replacementof lamps.

The indicia panel also serves, by its construction, to aid in thedissipation of heat and to limit the flow of light from each bulb to itsrespectively associated indicia section. As best shown in FIGS. 5 and 6the rear face of the indicia panel is recessed in regions underlying theseveral indicia sections and in an area overlying the bores or openingsthrough the shield and heat sink units. This relationship is shown inperspective at the left front of the unit illustrated in FIG. 1. Therecess behind the indicia section 60 is designated by the referencenumeral in FIGS. 5 and 6. Advantageously, as shown, the recess iscircular and has the same diameter and is formed on the same axis as thelamp opening of the shield and heat sink unit which it overlies. Therecess extends nearly through the front panel section so that the depthof the indicia section is relatively small. The indicia sectioncomprises an opening through the indicia panel from its front face tothe recess behind. The opening thus formed is filled with a lightconducting material, of any desired color, and advantageously comprisesa transparent or transluscent plastic material as shown. Thisconstruction, that is the provision of a recess, serves to elongate theopening in which the lamp bulb is housed and to limit the depth of theindicia openings. This construction permits the use of a thicker andtherefore stronger indicia panel while providing maximum interiorsurface to absorb radiant energy or to reflect light rays to exit at theindicia opening. ln addition this construction results in the flow oflight from the lamp to the indicia opening both directly and afterreflection so that the light impinges upon the rear face of the indiciaopening from all directions permitting indicia openings with dimensionsextending beyond the limits of the recess which it overlies. In FIG. theline segments 60 is shown in transverse section to have a width verymuch smaller than the diameter of the recess 140. However, in FIG. 6this line segment 60 is shown to have a length which exceeds insubstantial degree the diameter of recess I40. Nonetheless it will beapparent that light rays emanating from lamp 26 and flowing directly orafter reflection, will illuminate all portions of the front face of theline segment 60.

lclaim: V

1. ln a lighted display unit in combination:

an indicia panel formed with indicia sections capable of transmittinglight transversely through said panel but being otherwise opaque;

a lamp socket and a lamp socket holder assembly comprising a lamp socketholder having a plurality of lamp sockets mountedon one face thereof anddisposed in positions corresponding to the position of the indiciasections of said indicia panel;

a lamp shield and heat sink unit interposed between said indicia paneland said lamp socket holder panel;

said lamp shield being provided with a plurality of through openings,one for each indicia section of said panel and underlying itsrespectively associated indicia section;

a plurality of lamps having electrical connections connected toarespectively associated one of said lamp sockets and disposed'each in arespectively associated one of said through openings of said lampshield; and

a mountingplate interposed between said lamp shieldand said lamp socketholder, said mounting plate being provided with a through opening ofsize to accommodate all of said lamp and through which all of said lampsextend.

2. The invention defined in claim 1, including fastening means forsecuring said indicia panel and said lamp shield to one side of saidmounting plate and removable from the panel side of the assembledcombination of the panel, shield and plate, and means for securing saidsocket holder assembly to the other side of said mounting plate andremovable from the socket holder side of said assembled combination ofthe holder and plate.

3. The invention defined in claim I, in which said indicia sections areseven in'number and have the shape of line segments arranged in acluster defining, when said display unit is oriented vertically, thenumeral 8; said lamp shield and socket holder assembly 'each comprisinga central section aligned with the cluster and end sections offsetlaterally in the same direction from said central portion of said lightshield and socket holder.

4. The invention defined in claim 3, in which said indicia panelscomprise additional indicia sections overlying, in part, said laterallyoffset upper and lower sections of said lamp shield and socket holderand in which the upper and lower sections of the shield are formed withadditional openings of size to accommodate lamps aligned with saidadditional sections and in which the socket holder includes lamp socketsaligned with said additional openings.

5. The invention defined in claim 4 in which said additional sectionsare generally circular and capable of representing degree and decimalmark; and in which the openings through said shield are circular.

6. In a lighted display unit in combination: I an indicia panel arrangedfor vertical mounting and comprising nine light conducting sectionscapable of transmitting light from the rear to the front face of saidpanel, said indicia sections being separated by opaque sections of thepanel; seven indicia sections having the form of a line segment, theline segments of three of said seven sections being arranged in spacedparallel relation to define the top, center and lower horizontalportions respectively of a figure 8 and the other indicia sections ofthe seven sections being arranged in pairs to define the sides of theupper and lower sections of said figure 8;

two indicia sections of the nine sections being arranged at one side ofsaid seven sections on a line parallel with said three of said sevensections and disposed adjacent the sections representing said top andlower horizontal portions of said FIG. 8;

lighting means associated with each of said indicia sectionsrespectively for directing light to the indicia section with which it isassociated and to no other upon the applica-. tion of energy thereto;and

a housing containing said lighting means and having a central portionunderlying said seven indicia sections and top and lower portions offsetlaterally from said center portion toward the side corresponding to saidone side at which said two indicia sections are arranged relative tosaid seven indicia sections.

7. The invention defined in claim 6, said housing further comprising alamp socket holder and lamp socket assembly unit including'nine socketsadapted to receive terminals of a lamp and located, respectively, onebehind each of said nine display sections;

said housing further comprising a separable output terminal assemblyhousing on one side of said socket holder and lamp socket assembly unit;

said sockets each having portions extending into said output terminalassembly and each comprising an insulating sleeve fonned with twoopenings along its length and a metal connector sleeve lanced along aportion of its length and inserted into a respectively associated one ofsaid two openings; and

said invention further comprising a mounting plate to which said indiciapanel is secured at one side and to whose other side said lamp socketholder and lamp socket assembly is secured.

1. In a lighted display unit in combination: an indicia panel formedwith indicia sections capable of transmitting light transversely throughsaid panel but being otherwise opaque; a lamp socket and a lamp socketholder assembly comprising a lamp socket holder having a plurality oflamp sockets mounted on one face thereof and disposed in positionscorresponding to the position of the indicia sections of said indiciapanel; a lamp shield and heat sink unit interposed between said indiciapanel and said lamp socket holder panel; said lamp shield being providedwith a plurality of through openings, one for each indicia section ofsaid panel and underlying its respectively associated indicia section; aplurality of lamps having electrical connections connected to arespectively associated one of said lamp sockets and disposed each in arespectively associated one of said through openings of said lampshield; and a mounting plate interposed between said lamp shield andsaid lamp socket holder, said mounting plate being provided with athrough opening of size to accommodate all of said lamp and throughwhich all of said lamps extend.
 2. The invention defined in claim 1,including fastening means for securing said indicia panel and said lampshield to one side of said mounting plate and removable from the panelside of the assembled combination of the panel, shield and plate, andmeans for securing said socket holder assembly to the other side of saidmounting plate and removable from the socket holder side of saidassembled combination of the holder and plate.
 3. The invention definedin claim 1, in which said indicia sections are seven in number and havethe shape of line segments arranged in a cluster defining, when saiddisplay unit is oriented vertically, the numeral 8; said lamp shield andsocket holder assembly each comprising a central section aligned withthe cluster and end sections offset laterally in the same direction fromsaid central portion of said light shield and socket holder.
 4. Theinvention defined in claim 3, in which said indicia panels compriseadditional indicia sections overlying, in part, said laterally offsetupper and lower sections of said lamp shield and socket holder and inwhich the upper and lower sections of the shield are formed withadditional openings of size to accommodate lamps aligned with saidadditional sections and in which the socket holder includes lamp socketsaligned with said additional openings.
 5. The invention defined in claim4 in which said additional sections are generally circular and capableof representing degree and decimal mark; and in which the openingsthrough said shield are circular.
 6. In a lighted display unit incombination: an indicia panel arranged for vertical mounting andcomprising nine light conducting sections capable of transmitting lightfrom the rear to the front face of said panel, said indicia sectionsbeing separated by opaque sections of the panel; seven indicia sectionshaving the form of a line segment, the line segments of three of saidseven sections being arranged in spaced parallel relation to define thetop, center and lower horizontal portions respectively of a figure 8 andthe other indicia sections of the seven sections being arranged in pairsto define the sides of the upper and lower sections of said Figure 8;two indicia sections of the nine sections being arranged at one side ofsaid seven sections on a line parallel with said three of said sevensections and disposed adjacent the sections representing said top andlower horizontal portions of said FIG. 8; lighting means associated witheach of said indicia sections respectively for directing light to theindicia section with which it is associated and to no other upon theapplication of energy thereto; and a housing containing said lightingmeans and having a central portion underlying said seven indiciasections and top and lower portions offset laterally from said centerportion toward the side corresponding to said one side at which said twoindicia sections are arranged relative to said seven indicia sections.7. The invention defined in claim 6, said housing further comprising alamp socket holder and lamp socket assembly unit including nine socketsadapted to receive terminals of a lamp and located, respectively, onebehind each of said nine display sections; said housing furthercomprising a separable output terminal assembly housing on one side ofsaid socket holder and lamp socket assembly unit; said sockets eachhaving portions extending into said output terminal assembly and eachcomprising an insulating sleeve formed with two openings along itslength and a metal connector sleeve lanced along a portion of its lengthand inserted into a respectively associated one of said two openings;and said invention further comprising a mounting plate to which saidindicia panel is secured at one side and to whose other side said lampsocket holder and lamp socket assembly is secured.